update_invoice

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description is the sole source. Only indicates it's a write operation via '[WRITE]'. No details on side effects, permissions, or state constraints (e.g., can you update a VOIDED invoice?).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence, no fluff. Front-loaded with '[WRITE]' for quick classification. Efficient for its length.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given 8 parameters, nested objects, and no output schema, the description is too brief. It omits return value, error handling, required permissions, and behavior when invoice is in certain states. Insufficient for a complex tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 75% (most parameters have descriptions). The description adds value by summarizing updatable fields but does not elaborate on parameter semantics beyond the schema. For instance, 'lineItems' says 'Replaces the line items if supplied' in schema, but description doesn't expand.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states the action 'Update an invoice by invoiceID' with examples (status, reference, due date, line items). Distinguishes from siblings like create_invoice (write) and get_invoice (read).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No explicit guidance on when to use vs alternatives. Does not mention prerequisites or when not to use (e.g., invoice already voided). Context only implied by examples.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.